In recent years there has been a growing trend to improve fuel efficiency of a vehicle such as an automobile by reducing the weight thereof, and accordingly, weight reduction of a wire material constituting a wire harness is also demanded. Thus, the use of aluminum for a conductor has been studied.
However, for terminal fittings, generally, copper or a copper alloy, which has excellent electrical characteristics, is used. Therefore, a combination of an aluminum wire and a copper terminal fitting, or the like is often used. When a conductor and a terminal fitting are made of different materials, corrosion due to contact between dissimilar metals occurs at an electrical connection portion therebetween. This type of corrosion is more likely to occur compared with the case where the conductor and the terminal fitting are made of the same material. Thus, an anticorrosive agent capable of reliably preventing corrosion of the electrical connection portion is necessary.
In order to prevent corrosion at the above-described electrical connection portion, for example, a technique of sealing an exposed portion of a conductor (core wire) at a leading end portion of an aluminum wire by using a silicon resin or an acrylic resin is known from Patent Document 1 (JP 2011-238500A).